package com.hmdp.utils;

import cn.hutool.core.lang.UUID;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.data.redis.core.script.RedisScript;

import java.util.Collections;
import java.util.concurrent.TimeUnit;

public class SimpleRedisLock implements ILock {

    private static final String KEY_PREFIX = "lock:";
    private static final String ID_PREFIX = UUID.randomUUID().toString(true) + "-";
    private final String name;
    private final StringRedisTemplate stringRedisTemplate;
    //  导入Lua脚本
    private static final DefaultRedisScript<Long> UNLOCK_SCRIPT;
    static {
        UNLOCK_SCRIPT = new DefaultRedisScript<>();
        UNLOCK_SCRIPT.setLocation(new ClassPathResource("unLock.lua"));
        UNLOCK_SCRIPT.setResultType(Long.class);
    }


    public SimpleRedisLock(String name, StringRedisTemplate stringRedisTemplate) {
        this.name = name;
        this.stringRedisTemplate = stringRedisTemplate;
    }

    @Override
    public boolean tryLock(long expiredTime) {
        String id = ID_PREFIX + Thread.currentThread().getId();
        Boolean set = stringRedisTemplate.opsForValue().setIfAbsent(KEY_PREFIX + name, id, expiredTime, TimeUnit.SECONDS);
        return Boolean.TRUE.equals(set);
    }

    @Override
    public void unLock() {
        stringRedisTemplate.execute(
                UNLOCK_SCRIPT, Collections.singletonList(KEY_PREFIX + name), ID_PREFIX + Thread.currentThread().getId()
        );
    }

    //    @Override
//    public void unLock() {
//        String id = stringRedisTemplate.opsForValue().get(KEY_PREFIX + name);
//        String s = ID_PREFIX + Thread.currentThread().getId();
//        if (id != null && id.equals(s)){
//            stringRedisTemplate.delete(KEY_PREFIX + name);
//        }
//    }
}
